Communication-based monitoring of compliance with aviation regulations and operating procedures

ABSTRACT

A method for detecting noncompliance with aviation regulations and operating procedures is disclosed herein. The method analyzes communication associated with a host aircraft to identify key information, stores the identified key information in a data storage device, and determines whether a particular aviation regulation or operating procedure applies to the host aircraft. After determining that a regulation or operating procedure applies, the stored key information is compared against reference information maintained in a database in association with the regulation or operating procedure. An alert is generated when the comparing detects a discrepancy between the stored key information and the reference information.

TECHNICAL FIELD

Embodiments of the subject matter described herein relate generally toavionic systems. More particularly, embodiments of the subject matterrelate to systems and methods for detecting pilot compliance bymonitoring cockpit communications.

BACKGROUND

The cross-checking process is used in aviation environments to reducethe likelihood of errors. The ultimate goal of a cross-check is toprevent errors related to execution of a collaborative decision byinvolving another party into the action execution. The cross-checkingprocess conventionally involves verbal and visual verification of anintended action in the cockpit prior to its execution. Even thoughcockpit systems are in many cases “smart” enough to not allow executionof a hazardous action by a flight crew member (system-based crosscheck),many actions still rely on pilot verification of the action correctness(human-based crosscheck).

The cross-checking process is a vital element in a pilot's duties,particularly in a multi-crew situation. There is typically a minimumlist of defined actions which are to be cross-checked. For example, airtraffic control (ATC) clearances and other requests/instructions willnormally be monitored by both pilots, and consequent pilot action takenby the pilot flying (PF) will be confirmed or monitored by the pilot notflying (PNF). Equipment settings, such as altimeter pressure settings,cleared altitude, frequency change, and navigation routings are alsotypically set by the PNF and cross-checked by the PF, or vice versa. Insingle pilot operations (SPO), there is no cross-checking second pilot.

Unfortunately, while the cross-checking process can significantly reducethe likelihood of errors, there are many examples where human-basedcross-checking may not be adequate. The human mind is fallible and humanerror can occur for many reasons. For example, the cross-checkingprocess may fail because of a misheard message, fatigue, a memory lapse,incorrect or incomplete appreciation of the situation, insufficientcross-check, language barriers, distraction, communication problems,ineffective monitoring, data use error, non-compliance with standardoperating procedures (SOPs), etc. Cross-checking errors are more likelyin certain circumstances such as when there is pressure to complete anaction quickly (e.g., to expedite departure or during an emergency orabnormal situation), but may also occur in normal daily situations.

Accordingly, it is desirable to provide aircraft systems and methods fordetecting non-compliant pilot action. In addition, it is desirable toprovide methods and systems for cross-checking compliance with aviationregulations, airspace restrictions, and the like. Furthermore, otherdesirable features and characteristics of the methods and systems willbecome apparent from the subsequent detailed description and theappended claims, taken in conjunction with the accompanying drawings andthe preceding background.

BRIEF SUMMARY

A computer-implemented method for detecting noncompliance with aviationregulations and operating procedures is presented herein. The methodanalyzes communication associated with a host aircraft to identify keyinformation contained in the communication, and stores the identifiedkey information in a data storage device to obtain stored keyinformation. The method continues by determining that a particularaviation regulation or operating procedure applies to the host aircraft.After making the determination, the method compares the stored keyinformation against reference information maintained in a database inassociation with the particular aviation regulation or operatingprocedure. An alert is generated when the comparing detects adiscrepancy between the stored key information and the referenceinformation.

Also presented herein is a tangible and non-transitory electronicstorage medium having processor-executable instructions that, whenexecuted by a processor architecture comprising at least one processordevice, are capable of performing the method of detecting noncompliancewith aviation regulations and operating procedures.

Also presented herein is a computer-implemented system for detectingnoncompliance with aviation regulations and operating procedures. Thesystem includes a processor architecture having at least one processordevice, and at least one data storage device associated with theprocessor architecture. The at least one data storage device storesprocessor-executable instructions that, when executed by the processorarchitecture, perform the method of detecting noncompliance withaviation regulations and operating procedures.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the subject matter may be derived byreferring to the detailed description and claims when considered inconjunction with the following figures, wherein like reference numbersrefer to similar elements throughout the figures.

FIG. 1 is a schematic diagram of a computer-implemented system fordetecting non-compliant pilot action, according to an exemplaryembodiment; and

FIG. 2 is a flow chart that illustrates an exemplary embodiment of acomputer-implemented process that detects noncompliance with aviationregulations and operating procedures.

DETAILED DESCRIPTION

The following detailed description is merely illustrative in nature andis not intended to limit the embodiments of the subject matter or theapplication and uses of such embodiments. As used herein, the word“exemplary” means “serving as an example, instance, or illustration.”Any implementation described herein as exemplary is not necessarily tobe construed as preferred or advantageous over other implementations.Furthermore, there is no intention to be bound by any expressed orimplied theory presented in the preceding technical field, background,brief summary or the following detailed description.

Techniques and technologies may be described herein in terms offunctional and/or logical block components, and with reference tosymbolic representations of operations, processing tasks, and functionsthat may be performed by various computing components or devices. Suchoperations, tasks, and functions are sometimes referred to as beingcomputer-executed, computerized, software-implemented, orcomputer-implemented. It should be appreciated that the various blockcomponents shown in the figures may be realized by any number ofhardware, software, and/or firmware components configured to perform thespecified functions. For example, an embodiment of a system or acomponent may employ various integrated circuit components, e.g., memoryelements, digital signal processing elements, logic elements, look-uptables, or the like, which may carry out a variety of functions underthe control of one or more microprocessors or other control devices.

When implemented in software or firmware, certain features of thesystems described herein can be represented by the code segments orinstructions that perform the various tasks. In certain embodiments, theprogram or code segments are stored in a tangible processor-readablemedium, which may include any medium that can store or transferinformation. Examples of a non-transitory and processor-readable mediuminclude an electronic circuit, a semiconductor memory device, a ROM, aflash memory, an erasable ROM (EROM), a floppy diskette, a CD-ROM, anoptical disk, a hard disk, or the like.

Various embodiments are directed to methods and systems for detectingnon-compliant pilot action. In particular, the systems and methodologiespresented herein can be utilized to confirm whether or not a pilot hascomplied with applicable aviation regulations, operating procedures, andthe like. Such methods and systems provide an additional cross-check,which is particularly helpful in Single Pilot Operations. By detectingnon-compliant pilot action, the methods and systems as described hereinhelp correct non-compliant pilot action, thereby resulting in increasedflight safety and efficiency through more effective communications.While systems and methods for detecting non-compliant “pilot” action arehereinafter described, it is to be understood that such systems andmethods may be used for detecting non-compliant action taken by a flightmember other than the pilot.

Requests for pilot action may originate from a ground location such asair traffic control (ATC), or from another source. While the term“request” for pilot action is used herein, it is to be understood thatany inbound communication to the aircraft that must be acknowledged insome manner by the pilot in an outbound communication from the aircraftis included, whether it is literally an instruction, a request, acommand, or the like. The term “pilot action” refers to the action thatis taken by the “pilot” and intended to be compliant with the inboundcommunication from ATC or another source. In accordance with exemplaryembodiment, “pilot action” refers to a parameter as hereinafterdescribed and a value associated with the parameter (i.e., a “parametervalue”). “Non-compliant pilot action” for this scenario may include afailure to correctly follow an ATC request (i.e., a failure to take thecorrect pilot action), a failure to follow an ATC request afteracknowledgement thereof by the pilot resulting in a timeout alert (i.e.,a failure to take the pilot action), or both. As explained in moredetail below, non-compliant action may also be associated with failureto comply with certain aviation regulations or operating procedures, andsuch non-compliant action can be detected by monitoring other forms ofcockpit communication (inbound and/or outbound communication).

The system and methodologies described herein can analyze various typesof cockpit communication for purposes of performing consistency checks.In this regard, the monitored communication may include speech, voiceradio communication, electronic communication (e.g., datalinkcommunication), or the like. For example, some or all of the followingcommunication types can be considered, without limitation: instructionsreceived from ATC, such as ARTCCs, towers, FSSs, Central Flow, andOperations Centers; flight crew responses to ATC instructions, wherein aresponse can include instruction or clearance read back, informationacknowledgement, and instruction rejections; other flight crew andground crew conversations over UNICOM; ground broadcast information fromATC, such as wind information, barometric correction settings, and thelike, ATIS, UNICOM, ASOS, AWSS, and AWOS; flight crew self-announcedinformation on CTAF, which may include UNICOM, MULTICOM, FSS, towerfrequency, and other air-to-air communication (122.75 for private fixedwing aircraft, 123.025 for general aviation helicopters, etc.).

As used herein, an “aviation regulation” is a rule or directive that isproduced and published by a recognized authority, such as a FederalAviation Regulation (FAR) for the United States.

As used herein, an “aviation operating procedure” refers to arecommended and common piloting practice, which can be defined by one ormore aviation regulations. For example, FAR Part 91 relates to generaloperating and flight rules.

The system may be utilized in aircraft, such as a helicopter, airplane,or unmanned vehicle. Moreover, exemplary embodiments of the system mayalso be utilized in spacecraft, watercraft, submarines, and other typesof vehicles, in addition to machine operation. For simplicity, thenon-limiting embodiments are described below with reference to aircraft.

FIG. 1 is a simplified functional block diagram of acomputer-implemented system 10 for detecting non-compliant pilot action,according to exemplary embodiments of the present invention. The system10 includes multiple components, each of which may be configured formounting in a host aircraft. In some embodiments, the system 10 may be aself-contained system such that each of the components described belowis contained in a single housing and is dedicated exclusively to servingthe functions of the system 10. In other embodiments, the variouscomponents described below may be standalone components or they may becomponents that are used as part of other systems and which areconfigured to be used as a shared resource between such other systemsand the system 10. For example, the system 10 can be realized using anintegrated avionic system, or it can also be a laptop computer, a tabletcomputer, or a mobile device that interfaces to various onboard avionicssystems and sensors, and that has been programmed in a particular mannerto support the specialized functions and features described in moredetail below.

In the embodiment illustrated in FIG. 1, the system 10 includes acommunication system 12, a recognition module 14 (which can detect,recognize, or otherwise analyze speech, voice radio communication,navigation aid signals, or the like), a flight management system 16, auser interface 18, a processor device 20, a data storage device 22, anda display device 24. In other embodiments, the system 10 may includeeither additional or fewer components. For example, the system 10 caninclude other annunciation or notification devices or components inaddition to, or in lieu of, the display device 24. The system 10 may bearranged as a single system on a data communications bus or systems busor in an arrangement whereby one or more of the communication system 12,the processor device 20, the speech recognition module 14, the datastorage device 22, the flight management system 16, the display device24, and the user interface 18 are separate components or subcomponentsof another system located either onboard or external to an aircraft. Itshould be understood that FIG. 1 is a simplified representation of thesystem 10 for purposes of explanation and ease of description, and thatFIG. 1 is not intended to limit the application or scope of the subjectmatter in any way. In practice, while not illustrated, the system 10and/or the host aircraft may include either additional or fewer devices,components, and databases for providing system functions and features,as will be appreciated in the art.

Still referring to FIG. 1, in exemplary embodiments, the communicationsystem 12 is suitably configured to support communications between theaircraft (e.g., the pilot or the flight crew) and one or more groundlocations (e.g., ATC). The communication 12 can also be configured tosupport air-to-air communication. The communication system 12 may berealized using a radio communication system 26 and/or a datalink system28 (as hereinafter described). In accordance with certain embodiments,the communication system 12 can support any number of communicationprotocols, methodologies, and technologies, as is well understood. Forexample, the communication system 12 can support any or all of thefollowing, without limitation: intercomm communication; satellite voicecommunication; radio communication; navigation radio communication; VHFdatalink communication; satellite data communication;aircraft-to-aircraft communication; and the like.

Communication from a ground location to the aircraft is referred toherein as an “inbound communication”. Communication received at the hostaircraft from a neighboring aircraft (air-to-air transmission) is alsoconsidered to be an “inbound communication”. Communication from the hostaircraft to a ground location or another aircraft is referred to hereinas an “outbound communication.” The standard method of communicationbetween ATC and the pilot is voice radio, using the radio communicationsystem 26 (VHF bands for line-of sight communication, or HF bands forlong-distance communication, or satellite communication). The radiocommunication system 26 in the cockpit may include, for example, aconventional speaker and microphone that may be combined in an aviationheadset (not shown), a radio receiver (not shown), and a push-to-talk(PTT) switch (not shown).

The sequence of messages between the aircraft and the ground locationrelating to a particular transaction (for example a request for pilotaction and acknowledgment of the request) is termed a “dialog”. Therecan be several sequences of messages in the dialog, each of which isclosed by means of appropriate messages, usually of acknowledgement oracceptance. All exchanges of messages between the aircraft and theground location can be viewed as dialogs. The messages may relate to avariety of parameters such as a heading, an altitude, attitude, flightlevel, or QNH, and a parameter value associated therewith. For example,the air traffic controller (ATCO) is provided with the capability toissue level assignments, crossing constraints, lateral deviations, routechanges and clearances, speed assignments, radio frequency assignments,various requests for information, etc. The pilot is provided with thecapability to acknowledge the request for pilot action, respond tomessages, to request clearances and information, to report information,and to declare/rescind an emergency. Passively received groundbroadcasts or communication between the aircraft and a ground-based“non-control” facility can also be considered as another importantsource of information that can be monitored by the system describedherein.

Controller-pilot datalink communications (CPDLC) are digitalcommunications and are another method of communication between the ATCand the pilot, using the datalink system 28 for such digitalcommunication. For example, the ATC can select from a set of messagesand send the digital communications to the aircraft (via the processordevice 20 in this case). The flight crew will respond with anacknowledgment, such as ROGER, WILCO, STANDBY, or NEGATIVE. The pilotis, in addition, provided with the capability to request conditionalclearances (downstream) and information from a downstream air trafficservice unit (ATSU). A “free text” capability is also provided toexchange information not conforming to defined formats. An auxiliarycapability is provided to allow a ground system to use the datalinksystem to forward a CPDLC message to another ground system. The cockpitincludes a datalink control and display device (not shown) that servesas the CPDLC interface for sending and receiving CPDLC messages. Thedatalink system 28 sends digital signals from the CPDLC for processingby the processor as hereinafter described.

The system can also monitor and process navigational aid broadcastinformation if so desired. In this regard, a VOR system, a DME system,and an NDB system normally transmit audible Morse code along with thenavigational aid signals to assist the pilot in positively identifyingthe correctness of the tuned navigational aid, and to confirm itshealthy status. Monitoring and analyzing this type of navigation systembroadcast information can be performed to check compliance with aviationregulations and/or operating procedures as needed.

The speech recognition module 14 monitors audible communications(inbound and/or outbound) to detect when certain words, phrases,letters, etc. are annunciated. As explained in more detail below, thespeech recognition module 14 can be suitably designed to “listen” forparticular keywords or key phrases that implicate compliance (ornoncompliance) with aviation regulations and operating procedures thatmay be currently applicable. The speech recognition module 14 is knownand generally comprises a speech input module configured to produce adigital signal derived from a voice communication, and a speechprocessing module operatively coupled to the speech input module. Thedigitized speech sample can be compared against a library of storedsamples that correspond to sounds, words, phrases, letters, codes,waypoint identifiers, airport identifiers, geographical identifiers, orthe like. In some embodiments, the speech recognition module 14 mayinclude a dedicated processor, a microprocessor, circuitry, or someother processing component. In some embodiments, the speech recognitionmodule 14 is configured to produce digital data that represents certaincontent (words or phrases) corresponding to the voice communicationsbetween ATC and the pilot. The speech recognition module 14 isconfigured to send the digital signal to the processor device 20 ashereinafter described.

The flight management system 16 is as known to one skilled in the art.The flight management system 16 includes the flight guidance controlsystem for the host aircraft. The flight management system 16 is coupledto the processor device 20 and may provide navigation data associatedwith the aircraft's current position and flight direction (e.g.,heading, course, track, etc.) to the processor device 20. The navigationdata provided to the processor device 20 may also include informationabout the aircraft's airspeed, altitude, pitch, flight path, intendeddestination, takeoff and landing information, and other important flightinformation, some of which is obtained from various sensors, devices,subsystems, or components onboard the host aircraft. In practice, theflight management system 16 may generate a flight plan for the aircraftthat includes segments between waypoints forming a flight path to adestination. The flight management system 16 may include any suitableposition and direction determination devices that are capable ofproviding the processor device 20 with at least the current position ofthe aircraft, the real-time direction of the aircraft in its flightpath, the waypoints along the flight path, and other important flightinformation (e.g., elevation, pitch, airspeed, altitude, attitude,etc.). Information can be provided to the processor device 20 by, forexample, an Inertial Reference System (IRS), Air-data Heading ReferenceSystem (AHRS), and/or a global positioning system (GPS).

In general, the user interface 18 is coupled to the flight managementsystem 16 and is located within the cockpit of the aircraft. The userinterface 18 and the flight management system 16 are cooperativelyconfigured to allow a user (e.g., a pilot or other flight crew member)to interact with the flight management system 16 and other components ofthe system 10 as hereinafter described. In accordance with an exemplaryembodiment, the user interface 18 may be realized as a flight guidancecontrol panel (FGCP) (or simply “guidance panel”) as known in the art.The user interface 18 may also be realized by a Control Display Unit(CDU) or Multifunction Control Display Unit (MCDU). These both allow forinput of parameters to the flight management system. In addition, theMCDU also allows for input to and control of radios, CPDLC, aircraftperformance parameters, etc. The FGCP facilitates user control of theflight control or autopilot system. In a typical operating scenario, theFGCP enables the user to control altitude, airspeed, heading/course, andvertical speed/flight path angle (along with certain selectablecombinations of these options). On the FGCP are controls and switchesfor setting different operational modes, parameters, and parametervalues, etc. Pilot action may include the setting of parameters andparameter values on the guidance panel or elsewhere.

The system 10 includes a suitably configured and arranged processorarchitecture having at least one processor device 20. Although FIG. 1shows a simplified implementation having only one processor device 20,the processor architecture can employ any number of distinct processordevices 20. The processor device 20 may be any type of computingcomponent, computing architecture or subsystem, microprocessor,collection of logic devices, or any other analog or digital circuitrythat is configured to calculate, and/or to perform algorithms, and/or toexecute software applications, and/or to execute sub-routines, and/or tobe loaded with and to execute any type of computer program. In thisregard, the processor device 20 can execute computer programinstructions that are stored on a tangible storage medium, such as ahard drive, an optical disc, a memory chip or device, and the like. Theprocessor device 20 may comprise a single processor or a plurality ofprocessors acting in concert. In some embodiments, the processor device20 may be dedicated for use exclusively with the system 10 while inother embodiments the processor device 20 may be shared with othersystems on board the aircraft. In still other embodiments, the processordevice 20 may be integrated into any of the other components of thesystem 10. For example, in some embodiments, the processor device 20 maybe a component of the speech recognition module 14.

The processor device 20 is communicatively coupled to the datalinksystem 28, the speech recognition module 14, and the data storage device22, and is operatively coupled to the display device 24. Suchcommunicative and operative connections may be effected through the useof any suitable means of transmission including both wired and wirelessconnections. For example, each component may be physically connected tothe processor device 20 via a coaxial cable or via any other type ofwire connection effective to convey electronic signals. In otherembodiments, each component may be communicatively connected to theprocessor device 20 across a bus or other similar communicationcorridor. Examples of suitable wireless connections include, but are notlimited to, a Bluetooth connection, a Wi-Fi connection, an infraredconnection or the like.

Being communicatively and/or operatively coupled with the datalinksystem 28, the speech recognition module 14, data storage device 22, anddisplay device 24 provide the processor device 20 with a pathway for thereceipt and transmission of signals, commands, instructions, andinterrogations to and from and each of the other components. Theprocessor device 20 is configured (i.e., being loaded with and beingcapable of executing suitable computer code, software and/orapplications) to interact with and to coordinate with each of the othercomponents of the system 10 for the purpose of detecting non-compliantpilot action as hereinafter described.

The processor device 20 accesses or includes the data storage device 22,which stores and maintains a database 30 with digital data relating tothe communication of interest (e.g., the inbound and outboundcommunications) between the aircraft and the ground location. The datastorage device 22 may be a memory device (e.g., non-volatile memory,disk drive, tape, optical storage device, mass storage device, etc.)that stores and updates the data as needed. The database 30 can beconsidered to be a library of sorts, wherein the library includesrelevant keywords, phrases, call letters, codes, and/or other audiblydistinguishable information that is relevant to aviation regulations andoperating procedures applicable to the aircraft at any given time. Forexample, the data contained in the library may represent suchinformation as the source of the inbound communication (e.g., ATC,pilot), the parameter that is the subject of a request for pilot action(e.g., ALTITUDE, HEADING, ATTITUDE, FLIGHT LEVEL, QNH, SPEED,TRANSPONDER SETTING, FREQUENCY CHANGE, MONITOR, etc.), the parametervalue (e.g., 180°, 10000 feet, etc.), words or phrases associated withthe acknowledgement of the request for pilot action (e.g., ROGER, WILCO,STANDBY, and NEGATIVE), the name or identity of the entity initiating acommunication, the name or identity of the entity being called, the nameor identity of a destination of the aircraft (e.g., an airport name orcall letters, a waypoint name or call letters, a city, etc.), or thetail number of the aircraft. The database 30 can also be utilized tostore other types of reference data, or the system can utilize orcooperate with additional databases if so desired. For example, thesystem can include or cooperate with one or more of the following,without limitation: a navigation database; an airport database;databases that contain communication target frequencies; databases fornational airspace systems. The system can employ any number of distinctand separate databases, depending on the configuration of the particularembodiment, and depending on the type of regulation or operatingprocedure being checked.

The data storage device 22 (or another memory device or component) canrepresent a tangible and non-transitory electronic storage medium havingprocessor-executable instructions stored thereon. When such instructionsare executed by a processor architecture including at least oneprocessor device (such as the processor device 20), they are capable ofperforming the various methods, processes, and functions described inmore detail herein. In this regard, the system 10 can be programmed toexecute software that effectively transforms what might be a generalpurpose computing platform into a specialized piece of equipment thatsupports the techniques, technologies, and methodologies presentedherein.

Generally, the processor device 20 receives and/or retrieves avionics,navigation, and flight management information (e.g., from the flightmanagement system 16, the communications system 12, or both), andinformation relating to the inbound and outbound communications (e.g.,from the recognition module 14, the datalink system 28, and/or the datastorage device 22 to the extent historical or buffered data isprocessed). In some embodiments, the processor device 20 executescomputer readable instructions to compare a request for pilot actionagainst the actual pilot action taken and determine if there is adiscrepancy between the request for pilot action and the pilot actiontaken. In certain embodiments, the processor device 20 executes computerreadable instructions to confirm whether or not any communication thatis required or recommended by aviation regulations or operatingprocedures has actually been performed. The system 10 outputs adiscrepancy alert if, as a result of a comparison, a determination ismade that there is some inconsistency, non-compliance by the pilot orflight crew, or the like. For example, if the ATCO communicates arequest for the pilot to fly heading 100°, and the pilot sets a headingof 110° (e.g., on the guidance panel 34), the system 10 can output adiscrepancy alert. As another example, if an aviation regulationmandates that a pilot initiate communication with the ATCO for a givensituation, and the system 10 determines that no communication has beenestablished, then the system 10 can generate an alert or display areminder message, as appropriate.

The system 10 can also compare the inbound and outbound communicationsof a dialog and determine if there is a discrepancy between them(assuming that the discrepancy is not otherwise detected at or by theground location). The system 10 can output a discrepancy alert if, as aresult of the comparison, a determination is made that there is adifference between the inbound and outbound communications. For example,if the ATCO communicates a request for the pilot to fly at a heading of100° and the pilot acknowledges a heading of 110° (before taking anyaction), the processor would output a discrepancy alert because there isa difference between the inbound and outbound communications between theATCO and the pilot.

A discrepancy alert generated by the system 10 may be, for example, avisual discrepancy alert, an aural discrepancy alert, a tactilediscrepancy alert, combinations thereof, etc. It should be understoodthat the exemplary techniques for outputting the discrepancy alertdescribed above are exemplary and do not comprise an exhaustive list oftechniques that may be employed by the system 10 to output thediscrepancy alert(s). The system can use the display device 24 togenerate visual alerts. Other devices, components, or subsystems (notshown in FIG. 1) can be employed to generate other types of alerts asneeded.

The processor device 20 may also function as a graphics displaygenerator to generate display commands based on algorithms or othermachine instructions stored in association with the processor device 20.In this regard, the processor device 20 can serve as a graphics driverto operate the display device 24. The display device 24 may include anydevice or apparatus suitable for displaying flight information or otherdata associated with operation of the aircraft. In accordance withexemplary embodiments, display commands may also represent visualdiscrepancy and timeout alerts. The processor device 20 generates thedisplay commands representing this data, and sends the display commandsto the display device 24 if visual alerts are to be outputted.

In accordance with an exemplary embodiment, the display device 24 is anaircraft flight display located within a cockpit of the aircraft. Thedisplay device 24 may be implemented using any one of numerous knowndisplay devices suitable for rendering textual, graphic, and/or iconicinformation in a format viewable by the pilot or other flight crewmember. Non-limiting examples of such display devices include variouscathode ray tube (CRT) displays, and various flat panel displays such asvarious types of LCD (liquid crystal display) and TFT (Thin FilmTransistor) displays. In stand-alone implementations, the display device24 can be realized as a laptop screen, a tablet computer touchscreen, ora mobile device screen. The display device 24 may additionally beimplemented as a panel mounted display, a HUD (Head-Up Display)Projection, or any one of numerous known technologies. It isadditionally noted that the display device may be configured as any oneof numerous types of aircraft flight deck displays. For example, it maybe configured as a multi-function display, a horizontal situationindicator, or a vertical situation indicator. Regardless of how thedisplay device 24 is implemented, it can include a display screen 32,which is controlled by the display device 24 and is used to render anytype of image including, but not limited to, textual, graphics, andiconic information. In some embodiments, the display device 24 mayinclude multiple display screens 32.

In certain embodiments, the processor device 20 can output a timeoutalert if a set time limit to take pilot action is exceeded. The timeoutalert reminds the pilot to take action (e.g., change flight settings,perform certain operations, or the like) after having acknowledged arequest for pilot action. For example, in a situation where the receivedcommand is “Cross (waypoint) at 15,000 feet”, the systems may look tosee if there is a setting in the FMS for that restriction, in the casethe FMS is engaged. The system may look at the guidance control panel tosee if the aircraft is in an altitude hold condition, with the correctsetting, if the GCP is engaged, or the system can actively watch thealtimeter during manually controlled flight, and decide if the trendingaircraft position will meet the command. In any case, the system canlook at the speed of the aircraft and decide a certain time or distancebefore the waypoint that the command will likely not be met and alertthe pilot. A timeout alert may be, for example, a visual timeout alert,an aural timeout alert, a tactile timeout alert, an augmented realitytimeout alert, or combinations thereof For example, a visual timeoutalert can be displayed on a crew alerting system (CAS) window on thedisplay screen 32.

The system may also create an alert based upon aircraft position. Forinstance, if the pilot receives an instruction to “Report reachingFlight Level 250”, then the system can monitor aircraft altitude andlook for an action from the pilot when the altitude is reached. If thepilot does not take action to notify ATC that the altitude has beenreached, then an alert can be generated. The same behavior can apply toany horizontal aircraft position. It should be understood that an alert,reminder, or message can be generated and rendered using any suitablemethodology or technology.

The system 10 is designed and configured to execute specialized computersoftware to monitor pilot/crew compliance with applicable aviationregulations and operating procedures. Certain aviation regulations andoperating procedures require (or recommend) communication between thehost aircraft and another party, typically the ATC or anotherground-based entity. In many situations, the mandatory communicationwill include predictable or predetermined words, phrases, call letters,or the like. For example, an aviation regulation may require the pilotto identify a destination airport by name, such as “PHOENIX” or“GLENDALE”. As another example an aviation operating procedure mayrecommend a communication that includes “FREQUENCY CHANGE APPROVED”before a switch to another frequency when the aircraft is departing butstill within Class D airspace. In this context, aviation regulations andoperating procedures of interest can be characterized by expected orpredictable content, which may be audible or electronically detectable.The content (or a portion thereof) may be the same for a regulation orprocedure across different flights and aircraft, or it may vary from oneflight to another and/or from one aircraft to another. For example, theintended destination of the host aircraft can change depending on theflight plan and the current position of the host aircraft. Conversely,if a given regulation or operating procedure applies to one and only onedestination airport, then the name of that airport can be considered tobe a fixed parameter for purposes of the compliance monitoringmethodology described herein.

The system 10 and related methodologies described herein are applied tomonitor cockpit communication, extract key information from themonitored communication, and verify the consistency of past, present,and future flight crew operations, and onboard system status, to theidentified key information. This allows the onboard system to report anyinconsistencies and issue alerts as needed. In certain embodiments, thesystem 10 analyzes voice radio communication and various datalinkcommunications, which can include (but are not limited to) thefollowing: instructions received from ATC; flight crew responses to ATCinstructions, e.g., instruction or clearance read back, informationacknowledgement, and instruction rejections; flight crew and ground crewconversations using the UNICOM system; ground broadcast information froma manned or automated equipment or facility; and self-announcedinformation from the flight crew.

Although the exemplary embodiments described here typically monitor andanalyze speech and datalink information, the navigation radio of theaircraft may transmit identification information which can be receivedby the onboard communication system, e.g., Morse code stationidentification. This type of information is also valuable to theproposed functionality of the system 10, which can check in thebackground if an intended navigation aid is functioning normally.

In certain implementations, the speech recognition module 14 is suitablyconfigured to carry out “template free” information identification. Inthis regard, traditional speech recognition techniques utilized in theaviation industry usually rely on templates of known voice commands or alimited syntax set for extracting commands or critical information fromthe monitored speech signals. In contrast, the system 10 describedherein can employ an exemplary fast destination recognition technique ifso desired. The fast destination recognition technique can be appliedindependently or in conjunction with other speech recognition techniquesto increase processing efficiency and to improve the speech recognitionaccuracy.

The fast destination recognition methodology takes advantage of certainpredictable characteristics of aviation communication. For example,aviation radio contact procedures require a specific format forinitiating contact. More specifically, the name of the facility beingcalled should always be the first piece of information delivered in acall. The fast destination recognition procedure presented here capturesthe first speech segment that occurs after a radio squelch (under theassumption that the initial speech segment should contain an utteranceof the facility being contacted). The initial speech segment is analyzedto extract recognizable key information contained in a dynamicallygenerated dictionary. The dynamic vocabulary dictionary is limited insize because it only contains key information that corresponds todestinations within a certain range of the aircraft's current position,as determined by the positional data of the host aircraft in an ongoingmanner. Thus, the speech recognition module 14 need not analyze a largeand voluminous database of potential key terms. Rather, the speechrecognition module 14 can analyze a relatively compact, but dynamicallygenerated, database that only contains key information that has beenfiltered in accordance with the current position of the aircraft. Thus,the system 10 need not waste any time searching for key terms that bearlittle to no practical significance.

The key information that is processed by the system 10 can include,without limitation: destination and source information, locationinformation, altitude or flight level information, direction data, speeddata, time information, radio frequency information, request orinstruction information, etc. Moreover, the absence of a requiredcommunication can also be considered for purposes of checkingcompliance. In certain practical applications, source and destinationinformation is deemed important for use with consistency checks, and thefast speech recognition methodology described above can be utilized todetect source and destination information. Additional key informationcan be identified by various speech recognition methods, and by dataanalysis methods, as appropriate to the particular embodiment.

Although the system 10 can monitor and analyze different types ofcommunication during a consistency check, the features and functionalitystressed herein relate to the monitoring of cockpit communication toverify compliance with applicable aviation regulations and operatingprocedures. In this regard, the following example represents one typicalscenario in which the system 10 compares cockpit communication againstkey information associated with aviation regulations and operatingprocedures. Although the communication presented in the followingexample is voice radio based, the concept is also applicable to othermeans of communication.

Example Scenario

A pilot is flying a small airplane from Payson, Arizona (airportidentifier: KPAN) to Gila Bend, Ariz. (airport identifier: E63). Afterthe transition to Scottsdale, Arizona (airport identifier: KSDL) Class Dairspace, the pilot tunes to the Phoenix Approach frequency planning fora Class B transition. However, the pilot notices that the PhoenixApproach is quite busy, and decides to re-route to the west to avoid theClass B airspace. The pilot notices the Luke Alert Area, and maintainsaltitude a little higher than 3,000 feet to keep clear of the GlendaleClass D airspace and the 5,000 foot Phoenix Class B airspace bottom. Thepilot tunes to the Glendale tower frequency and monitors the trafficinformation. The pilot also tunes to the Glendale ATIS frequencies,while muting the ATIS channel for better monitoring of towertransmissions, because the pilot is not planning to make the Class Dtransition.

At six miles away from Glendale, Ariz. (airport identifier: KGEU), theonboard system recognizes the Glendale altimeter setting of 29.40 fromthe muted VHF radio channel, and the consistency check functiondetermines that the number is not applied correctly because thealtimeter setting from Scottsdale 29.90 is still in use. At this time, amessage is generated: “Verify altimeter setting—29.40 KGEU info U”,accompanied by a tone or other warning sound.

At five miles away, the onboard system identifies an entry of GlendaleClass D airspace with position, velocity, time, and corrected altitude.The operational consistency check function searches through the voicerecords but finds nothing associated with “Glendale Tower” in theoutbound aircraft communication. Accordingly, an airspace violation ispredicted, and the system generates a message: “Class D AirspaceViolation”. This message can be rendered along with other messages, andan audible alert can also be annunciated: “Contact Glendale Tower121.0”. For this example, therefore, the pilot can scan the display,become immediately aware of the situation, and resolve the conflict byquickly contacting the Glendale tower.

The system 10 can check for compliance with any number of differentaviation regulations and operating procedures, subject to practicallimitations and capacities of the hardware, software, and equipment. Inpractice, each aviation regulation and each aviation operating procedureof interest can be associated with a respective database object or entryin the database 30 (see FIG. 1). A database object corresponding to agiven aviation regulation or operating procedure can include some or allof the following information, without limitation: a set of rules thatgovern or otherwise define the regulation or operating procedure;conditions/criteria that determine when the regulation or operatingprocedure is valid or applicable; time constraints or time limitsapplicable to stored key information to be analyzed for the regulationor operating procedure; a library of National Airspace System structure;navigational data; aviation system information; a library of words,phrases, letters, and/or character strings that represent the referenceinformation associated with the regulation or operating procedure(wherein detected key information can be compared against the referenceinformation); and data corresponding to alerts, messages, or responsesto be generated in the event of detected noncompliance with theregulation or operating procedure.

A particular aviation regulation or operating procedure can be“universal” in that it has general applicability to all aircraft (or toa majority of aircraft). Conversely, a particular aviation regulation oroperating procedure may have limited applicability. For example, oneregulation or operating procedure can apply to certain classes ofaircraft, while another regulation or operating procedure can apply tocertain flight plans, destinations, or the like. The system 10 can“filter” the set of aviation regulations and operating procedures asneeded such that only the applicable or relevant ones are considered atany given time.

FIG. 2 is a flow chart that illustrates an exemplary embodiment of acomputer-implemented process 200 that detects noncompliance withaviation regulations and operating procedures. The various tasksperformed in connection with the process 200 may be performed bysoftware, hardware, firmware, or any combination thereof Forillustrative purposes, the following description of the process 200 mayrefer to elements mentioned above in connection with FIG. 1. It shouldbe appreciated that the process 200 may include any number of additionalor alternative tasks, the tasks shown in FIG. 2 need not be performed inthe illustrated order, and the process 200 may be incorporated into amore comprehensive procedure or process having additional functionalitynot described in detail herein. Moreover, one or more of the tasks shownin FIG. 2 could be omitted from an embodiment of the process 200 as longas the intended overall functionality remains intact.

The following description of the process 200 assumes that the system 10has already been deployed, configured, and initialized for operation inthe manner explained above. Moreover, the process 200 assumes that thedatabase 30 has already been populated with the reference informationneeded to monitor the various aviation regulations and operatingprocedures of interest. During operation of the host aircraft, theprocess 200 can be performed in a virtually continuous manner at arelatively high refresh rate. For example, an iteration of the process200 could be performed once every two seconds (or less) such thatdisplays and/or other annunciating devices and components are updated inreal-time or substantially real time in a dynamic manner duringoperation of the aircraft, and such that alerts can be generated as soonas noncompliance with an aviation regulation or operating procedure isdetected.

The exemplary embodiment of the process 200 begins by obtaining thecurrent flight status data of the host aircraft (task 202) and thecurrent geographic position data for the aircraft (task 204). Tasks 202and 204 can involve various sensors, devices, subsystems, and componentsonboard the host aircraft. Moreover, tasks 202 and 204 may leverage thefunctionality of onboard processing modules that provide navigation orflight plan data, terrain data, and the like. The process 200 monitorsand analyzes aircraft communication (primarily outbound communicationfrom the cockpit, but also inbound communication in certain situations)in an ongoing manner (task 206). For example, task 206 can analyzeoutbound communication from the host aircraft to identify keyinformation contained in the outbound communication. Key informationthat is identified as being potentially relevant is stored or bufferedin the data storage device 22 for an appropriate amount of time (task208). As noted previously, the stored key information represents digitaldata that has been recognized by the system 10 as relating to one ormore aviation regulations or operating procedures of interest (e.g.,critical words, call letters, phrases, codes, or the like). The source(e.g., ATC, pilot, aircraft identifier) of the stored key informationmay also be stored in the data storage device 22 in association with thestored key information. In addition, time stamp data can be stored inassociation with the stored key information. If the communication is avoice communication (as opposed to a digital communication via thedatalink system), then task 206 uses the speech recognition module 14 toperform speech recognition on the voice communication to generate orproduce the digital data derived from the voice communication. If thecommunication is navigation radio information, then task 206 canidentify the communication by analyzing Morse code content. If thecommunication is an electronic message (e.g., a datalink messagetransmitted from the host aircraft to an ATC system), then task 206analyzes the electronic message to identify key information containedtherein. Digital communications via the datalink system 28 may bedirectly stored in the data storage device 22 or, in some embodiments,digital communication from the datalink system 28 can be analyzed by thesystem 10 to recognize a word or phrase as corresponding to a particularaviation regulation or operating procedure. If the word or phrase isrecognized in the digital communication from the datalink system 28, thedigital communication may then be stored in the data storage device 22.

The process 200 also determines that a particular aviation regulation oroperating procedure applies to the host aircraft (task 210). It shouldbe appreciated that the process 200 can be designed to monitor anddetect compliance with any number of regulations and operatingprocedures in a concurrent manner. For ease of description and for thesake of simplicity, this example focuses on only one regulation oroperating procedure. Task 210 can analyze the current flight status dataand/or the geographical position data collected at tasks 202 and 204.More specifically, the process 200 compares the obtained flight statusdata and/or the obtained position data against predetermined criteriaassociated with the aviation regulations and operating procedures ofinterest. In this regard, certain aviation regulations and operatingprocedures may be applicable only under relevant conditions (e.g.,during takeoff, during approach, while transitioning from one class ofairspace to another, etc.). Thus, task 210 checks whether the criteriafor a given regulation or operating procedure has been satisfied. If so,then the process 200 can continue by checking the applicableregulation(s) and operating procedure(s). If not, then the process 200need not waste time or processing resources and need not considerirrelevant regulations and operating procedures. Task 210 effectivelyserves as a triggering mechanism that manages the process 200 and thatregulates which aviation regulations and operating procedures need to beverified for compliance at any given time.

As one example, assume that the aircraft is approaching a runway withinClass D airspace, and is instructed “report four mile final” upon itsfirst call to the tower. This type of instruction is commonly used tocontrol air traffic. The system captures the incoming instruction andmonitors the progress of the aircraft, along with the cockpitcommunication. If the system fails to identify an outbound call such as“xxx tower, xxx, four mile final” when the aircraft is approaching thefour mile point, an appropriate annunciation is communicated to theflight crew.

As another example, assume that an inexperienced new pilot is planning aClass B transition, establishes radio communication with the tower, andthe tower responded with “standby”. Normally, for a Class D airspacetransition, a “standby” implies that two-way communication has beenestablished, and one can enter the Class D airspace. However, for ClassB airspace, the required clearance is in the form of “cleared into ClassBravo airspace”. Such clearance is required before the aircraft canenter Class B airspace. For this example, therefore, the system monitorsthe aircraft vector and predicts entry into the Class B airspace withinfifteen seconds. However, the system detected an inbound “standby”communication, but did not detect an inbound “cleared into”communication. For this scenario, the system communicates the situationto the pilot such that the pilot can take appropriate action to avoidviolating the Class B airspace.

Other applicable examples include scenarios where the system can be usedto check aircraft altitude and assigned altitude along with ATCinstructions for a Class B transition, while also monitoring theaircraft speed to confirm that the speed satisfies the maximum speedcriteria for a Class B transition. In this context, certain aircraftregulations specify the maximum allowable speed for airspacetransitions.

As yet another example, some Class D airspace degrades to Class G whenthe ATC controller is off duty. In such a situation, there will be norequirement for establishing two-way communication with the controller.However, the system can still monitor the current time and cross-checkwith the navigational database to determine if the controller is stilloffline at the moment of airspace transition. This may be desirable toremind the pilot if the airspace returns to Class D, and if the pilotdid not contact the tower before entering the airspace.

This description assumes that one particular aviation regulation oroperating procedure has been identified as being applicable to thecurrent scenario and time frame. Accordingly, the process 200 continuesby comparing at least some of the stored key information against thereference information maintained in the database 30 in association withthe particular aviation regulation or operating procedure (task 212). Inpractice, task 212 need not consider all of the stored key informationand, instead, task 212 can review stored key information that has beencollected during a most recent period of time, e.g., the last tenminutes, the last hour, or the like. In some embodiments, older storedkey information can be automatically deleted or removed, under theassumption that stale information is no longer relevant in an ongoingcontext (see task 218, which is described in more detail below). Asmentioned above, the reference information that is used as the basis forcomparison can include words, letters, phrases, codes, or characterstrings that represent any predetermined parameters. For example, thereference information for the particular aviation regulation oroperating procedure can include, without limitation: an identifier ofthe host aircraft, such as the tail number; an identifier of an intendeddestination of the host aircraft, such as an airport identifier, awaypoint identifier, or the name of a city; an identifier of acommercial airline; the name or an identifier of the pilot or crewmember; a value of a control, navigation, of flight parameter, such as aspecified altitude, heading, airspeed, or pitch angle; flight plansettings; or the like.

If the comparison performed at task 212 results in a discrepancy betweenthe stored key information and the reference information thatcorresponds to the particular aviation regulation or operating procedureunder scrutiny (the “Yes” branch of query task 214), then the system 10generates and provides a suitably formatted alert, message, ornotification (task 216). If the system 10 outputs a discrepancy alert,the pilot is alerted to an error or noncompliance with a specifiedregulation or procedure, and the system 10 can request corrective actionor compliance. It should be appreciated that a discrepancy alert may beproduced using any technique or subsystem. For example, a visualdiscrepancy alert can be displayed on the display device 24, on aguidance panel, on an augmented reality display, on a head-up display,or the like.

If there is no discrepancy between the stored key information and thereference information (the “No” branch of query task 214), then theprocess 200 can continue by removing the stored key information. Removalof the stored key information may be performed after a predefined periodof time lapses (task 218). In this regard, the stored key informationcan be maintained for analysis during one or more subsequent iterationsof the process 200, or until the system 10 determines that the storedkey information is no longer relevant to the current situation.Maintaining the stored key information for only a limited period of timeis desirable to increase processing efficiency and to otherwise improvethe performance of the system 10. It should be understood that removalof stored key information is not always necessary and that an embodimentof the system 10 can delete stored key information at any time (e.g.,after completion of the current flight plan, after the aircraft isshutdown, after the data storage device 22 is full to capacity, or thelike).

While at least one exemplary embodiment has been presented in theforegoing detailed description, it should be appreciated that a vastnumber of variations exist. It should also be appreciated that theexemplary embodiment or embodiments described herein are not intended tolimit the scope, applicability, or configuration of the claimed subjectmatter in any way. Rather, the foregoing detailed description willprovide those skilled in the art with a convenient road map forimplementing the described embodiment or embodiments. It should beunderstood that various changes can be made in the function andarrangement of elements without departing from the scope defined by theclaims, which includes known equivalents and foreseeable equivalents atthe time of filing this patent application.

1. A computer-implemented method for detecting noncompliance withaviation regulations and operating procedures, the method comprising:analyzing communication associated with a host aircraft to identify keyinformation contained in the communication; storing the identified keyinformation in a data storage device to obtain stored key information;determining that a particular aviation regulation or operating procedureapplies to the host aircraft receiving, by a processor from a database,reference information that is associated with the particular aviationregulation or operating procedure; after the determining, comparing, bythe processor, the stored key information against the referenceinformation; and generating an alert when the comparing detects adiscrepancy between the stored key information and the referenceinformation.
 2. The method of claim 1, wherein: the communicationcomprises a voice communication; and the analyzing step performs speechrecognition on the voice communication to identify key informationcontained in the voice communication.
 3. The method of claim 1, wherein:the communication comprises an electronic message transmitted from thehost aircraft to an air traffic control system; and the analyzing stepanalyzes the electronic message to identify key information contained inthe electronic message.
 4. The method of claim 1, further comprising:removing the stored key information from the data storage device whenthe comparing step detects no discrepancy between the stored keyinformation and the reference information.
 5. The method of claim 1,wherein the determining step comprises: obtaining flight status data ofthe host aircraft; and comparing the obtained flight status data againstpredetermined criteria associated with the particular aviationregulation or operating procedure.
 6. The method of claim 1, wherein thereference information for the particular aviation regulation oroperating procedure comprises an identifier of the host aircraft.
 7. Themethod of claim 1, wherein the reference information for the particularaviation regulation or operating procedure comprises an identifier of anintended destination of the host aircraft.
 8. The method of claim 1,further comprising: maintaining the stored key information in the datastorage device for a limited time period; and removing the stored keyinformation from the data storage device after the limited time periodlapses.
 9. A tangible and non-transitory electronic storage mediumhaving processor-executable instructions that, when executed by aprocessor architecture comprising at least one processor device, arecapable of performing a method of detecting noncompliance with aviationregulations and operating procedures, the method comprising: analyzingcommunication associated with a host aircraft to identify keyinformation contained in the communication; storing the identified keyinformation in a data storage device to obtain stored key information;determining that a particular aviation regulation or operating procedureapplies to the host aircraft; receiving reference information that isassociated with the particular aviation regulation or operatingprocedure, the reference information being maintained in a database;after the determining, comparing the stored key information against thereference information; and generating an alert when the comparingdetects a discrepancy between the stored key information and thereference information.
 10. The storage medium of claim 9, wherein: thecommunication comprises a voice communication; and the analyzing stepperforms speech recognition on the voice communication to identify keyinformation contained in the voice communication.
 11. The storage mediumof claim 9, wherein: the communication comprises an electronic messagetransmitted from the host aircraft to an air traffic control system; andthe analyzing step analyzes the electronic message to identify keyinformation contained in the electronic message.
 12. The storage mediumof claim 9, wherein the determining step comprises: obtaining flightstatus data of the host aircraft; and comparing the obtained flightstatus data against predetermined criteria associated with theparticular aviation regulation or operating procedure.
 13. The storagemedium of claim 9, wherein the method further comprises: maintaining thestored key information in the data storage device for a limited timeperiod; and removing the stored key information from the data storagedevice after the limited time period lapses.
 14. A computer-implementedsystem for detecting noncompliance with aviation regulations andoperating procedures, the system comprising: a processor architecturecomprising at least one processor device; and at least one data storagedevice associated with the processor architecture, the at least one datastorage device storing processor-executable instructions that, whenexecuted by the processor architecture, perform a method of detectingnoncompliance with aviation regulations and operating procedures, themethod comprising: analyzing communication associated with a hostaircraft to identify key information contained in the communication;storing the identified key information in a data storage device toobtain stored key information; determining that a particular aviationregulation or operating procedure applies to the host aircraft;receiving, by the at least one processor device, reference informationthat is associated with the particular aviation regulation or operatingprocedure, the reference information being maintained in a database;after the determining, comparing the stored key information against thereference information; and generating an alert when the comparingdetects a discrepancy between the stored key information and thereference information.
 15. The system of claim 14, wherein: thecommunication comprises a voice communication; and the analyzing stepperforms speech recognition on the voice communication to identify keyinformation contained in the voice communication.
 16. The system ofclaim 14, wherein: the communication comprises an electronic messagetransmitted from the host aircraft to an air traffic control system; andthe analyzing step analyzes the electronic message to identify keyinformation contained in the electronic message.
 17. The system of claim14, wherein the determining step comprises: obtaining flight status dataof the host aircraft; and comparing the obtained flight status dataagainst predetermined criteria associated with the particular aviationregulation or operating procedure.
 18. The system of claim 14, whereinthe reference information for the particular aviation regulation oroperating procedure comprises an identifier of the host aircraft. 19.The system of claim 14, wherein the reference information for theparticular aviation regulation or operating procedure comprises anidentifier of an intended destination of the host aircraft.
 20. Thesystem of claim 14, wherein: the stored key information is maintained inthe data storage device for a limited time period; and the stored keyinformation is removed from the data storage device after the limitedtime period lapses.